The invention relates to a power semiconductor module with active and/or passive components. In particular, the present invention relates to a power converter module.
Several such power semiconductor modules are known from the literature. To increase performance, reliability and service life while reducing manufacturing costs, different configuration methods for the individual components are absolutely essential.
Modern power semiconductor modules, which are the starting point of this invention, are modules without base plate, as described, for example, in DE 199 03 875 A1, consisting of:    a housing;    a ceramic substrate with metal coatings arranged on same in a “circuit-friendly” manner, which is produced, for example, according to the DCB (direct copper bonding) method;    components such as diodes, transistors, resistors or sensors, are directly bonded to this substrate by soldering;    bonding to connect the structured side of the components to other components, the substrate and/or connecting elements leading to the outside;    a sealing compound preferably consisting of a material such as silicone rubber for insulating the individual components from each other.
In such power semiconductor modules, configurations providing pressure contact means for facilitating thermal contact of the module with a heat sink have proven very advantageous. It was found that it is very difficult to control the quality of soldering joints, particularly those with a large surface. Variable joint quality is detrimental to the reliability and service life of the power semiconductor modules.
Pressure buildup in such pressure-contacted power semiconductor modules is achieved using a mechanically stable pressure plate. Depending on further developments, the generated pressure can be transmitted to the substrate by special designs of the pressure plate, such as shown in DE 196 48 562 C1, or by an elastic pressure accumulator according to DE 199 03 875 A1.
Known from DE 41 32 947 A1 are flexible circuit boards and the use of electrically conducting and/or insulating pastes in power semiconductor modules. These are used as substitutes for the ceramic 2 substrates and for joints between the components.
U.S. Pat. No. 4,180,828 discloses the connection between a component and the conductive strips of a substrate via a flexible film. The electrical contact between the film and the component or between the film and the conductive strips is established by soldering or adhesive bonding.
The manufacturing methods according to DE 196 48 562 C1 or DE 199 03 875 A1 have the disadvantages that, as customary in modern modules, a large number of components must be contacted with each other and/or with the substrate. This is achieved by means of a large number of individual bonded joints. It is quite common to see up to 10 bonded joints per component. Since these bonding joints are produced in series, this process is quite time-consuming, with the result that producing them accounts for a substantial portion of the manufacturing cost of the modules.
The manufacturing method according to DE 41 32 947 A1 involves a sometimes extremely complex layer design and also requires the continued use of classical soldering joints. It therefore does not ensure the efficient configuration of power semiconductor modules.
In accordance with U.S. Pat. No. 4,180,828, the flexible film is applied either to the component or the conductive strips of the substrate by soldering or adhesive bonding. The practical production of such soldering joints is difficult because the introduction of heat through the film requires special techniques to prevent the film from being damaged and/or destroyed.